<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <title>Title</title>
    <!--
        左上 右上 右下 左下,顺时针方向
        圆角 = 半径
    -->
    <style>
        div{
            width: 50px;
            height: 50px;
            margin: 30px;
            /* border: 10px solid red; */
            background: red;
            border-radius: 50px 0px 0px 0px;
        }
        img{
            border-radius: 160px;
        }
    </style>
</head>
<body>
<div></div>
<img src="images/cat4.jpg" alt="cat">
</body>
</html>